DIY and no more libraries.

Real-time audio processing.js

function dsp(time){
	var master=Math.sin(Math.PI*2*440*time)*Math.exp(-3*time);
	return master;
}
var audioContext=new AudioContext(),
    bufferSize=2048, //256,512,1024,2048,4096,8192,16384
    node=audioContext.createScriptProcessor(bufferSize,0,2), //bufferSize,inputChannels,outputChannels
    time=0;
node.onaudioprocess=event=>{
	var L=event.outputBuffer.getChannelData(0),
	    R=event.outputBuffer.getChannelData(1),
	    value;
	for(var i=0;i<bufferSize;i++){
		value=dsp(time+(i/audioContext.sampleRate));
		if(Array.isArray(value)){ //Stereo.
			L[i]=value[0];R[i]=value[1];
		}else{ //Mono.
			L[i]=value;R[i]=value;
		}
	}
	time+=bufferSize/audioContext.sampleRate;
};
node.connect(audioContext.destination);

But I've fixed it now. :^)